Which of the following domains do not need software vulnerability assessments to mitigate risk from software vulnerabilities? a. user domainb. lan domainc. workstation domaind. system/application domain

I dont think that these four do not need because When we are discussing risk management, you can examine domains separately. Each domain represents a specific target. Some attackers have the skill they focus on the User Domain. Other attackers may be experts in particular applications, so they focus on the System/Application Domain. Similarly LAN and Workstation Domain.

Explanation:                                                        

When a threat exploits a vulnerability it is a loss. The impact determine the severity of the loss. A threat is  potential to cause a loss.  Threat as any activity  represents a possible danger. Threats  cannot be destroyed, but they  controlled. Threats have independent probabilities.For example, an attacker  attacking Web servers hosted on Apache. There is a company that can stop this attacker from trying to attack. A company can reduce or eliminate vulnerabilities . Threats are  exploit vulnerabilities that result in the loss of confidentiality, integrity, or availability of a business asset. In other words, risks to confidentiality, integrity, or availability represent potential loss to an organization. Because of this, a significant amount of risk management is focused on protecting these resources.            

b and c ( ip address and port number)